1. Field of the Invention
This invention relates to surgical instruments and, more particularly, to a method of controllably repositioning organs and vessels within a body cavity to facilitate the performance of surgical procedures.
2. Background Art
It is common to perform a number of medical procedures on female patients without making an incision by using endoscopic techniques, to include a) laparoscopy to perform surgery on pelvic organs by passing a telescope (laparoscope) through a small abdominal incision (an artificial opening) to gain access to the pelvis and b) hysteroscopy to perform intrauterine surgery by introducing a telescope (hysteroscope) through the natural vaginal and cervical openings to access the uterus. In the case of laparoscopy, the surgeon needs to use a dependable uterine manipulator to reposition the uterus to permit access to the region at which a procedure is to be performed. In the case of hysteroscopy, stabilizing and maintaining the position of the telescope within the uterus permits the surgeon to perform intrauterine procedures without fatigue and with precision.
The need for uterine manipulation is most pronounced where the uterus assumes a retroverted position, which is common for woman who have borne children. The surgeon is required to place the retroverted uterus into an anterior position to carry out most intrauterine procedures.
Uterine manipulation may be effected during a procedure by the surgeon or by an assistant. It is difficult and counterproductive for the surgeon to both reposition the uterus with an instrument in one hand and perform the procedure through a separate instrument held by the other hand.
Further, because the uterus is flexible and tends naturally towards one orientation, i.e. the retroverted position, the surgeon must constantly maintain a repositioning force on the uterus throughout a procedure. Not only is this activity tiring, but it is very difficult for the surgeon to maintain a consistent orientation of the uterus, particularly when the surgeon is simultaneously carrying out what is normally a delicate medical procedure.
If the uterine manipulation is carried out by an assistant, other problems are created. The assistant takes up valuable space in an operating room and by being positioned in front of the surgeon between the legs of the patient may interfere with the surgeon's view of a monitor through which the surgeon is able to observe the procedure.
It is equally difficult and wasteful for an assistant to be dedicated to the tasks of positioning, and maintaining the desired position of, the uterus throughout a surgical procedure. This is because certain uterine positions are difficult to maintain with manual pressure and because conventional manipulators do not lend themselves to automatically holding a uterine position, thereby requiring constant manual pressure, which is awkward and causes fatigue.
A multitude of different instruments have been devised to reposition the uterus. In each of U.S. Pat. No. 3,877,433, to Librach, U.S. Pat. No. 4,000,743, to Weaver, and U.S. Pat. No. 4,022,208, to Valtchev, instruments are disclosed wherein the distal end of the instrument is repositionable by being pivoted as a unit relative to a main body. Each of these instruments requires a relatively complicated linkage that permits this repositioning. This linkage may add considerably to the cost of an instrument, reduce its reliability, and make it undesirably cumbersome.
A further problem with these prior art instruments is that they may be relatively difficult to operate in use. As can be seen in FIGS. 1 and 2 of Weaver, a substantial lengthwise force must be exerted on the operating wire to effect the pivoting of the distal end of the instrument. There is a relatively small moment arm for the pivoting which requires that a large force be exerted on the wire. It is thus prone to breakage.
It is very important that the surgeon be able to maintain a desired position for a uterus. In the event that the desired position of a uterus is not maintained, tension on the tissues is affected and access to the region at which a procedure is to be performed is impaired, complicating and undesirably lengthening the time necessary for the procedure. The surgeon risks damaging adjacent tissues and organs because of lack of proper visualization and absence of tension on the affected tissue planes.